(CNN) - Some retirees are learning some distressing news.
It turns out, their pension plans have been overpaying them for years. And now the plans want the money back, with interest.
For some retirees, it can mean owing tens of thousands of dollars.
And with little warning, their pension checks are being slashed to cover their debt.
Many of the retirees affected don't feel they should be penalized for someone else's errors.
But one of the pension plans say it is legally allowed to collect any overpayment, with interest, in order to protect the viability of the pension fund.
The pension plans for American Water Works Company retirees and Sheet Metal Workers Local Union No. 73 retirees are among those who noticed overpayment issues and are requiring repayment.
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